Preheat your oven to 350°F. Lightly grease an 8" square or 9" round pan that's at least 2" deep., Whisk the dry ingredients together in a medium-sized bowl. Whisk the vanilla, vinegar, vegetable oil, and water in a separate bowl. Pour the wet ingredients into the bowl of dry ingredients, stirring until thoroughly combined. Pour the batter into the prepared pan., Bake the cake for 30 to 35 minutes, until a toothpick inserted into the center comes out clean, or with a few moist crumbs clinging to it., Serve the cake right from the pan; warm from the oven, it's wonderful with a big glass of milk., Or, once cool, frost the cake with this simple chocolate frosting: Heat the chocolate chips with the half-and-half until the chips melt. Stir until smooth, and pour/spread over the cake. For a non-dairy icing, substitute 1/3 cup cold brewed coffee (or water) for the half-and-half., Store cake, well covered, at room temperature for several days; freeze for longer storage.